The result lifts Sydney to fifth spot and sets up a tantalising knock-out match against fourth-placed Melbourne Victory at Docklands on Good Friday. Central Coast Mariners will play Adelaide United in the other sudden-death final the following day.

Having missed out on a top-six spot on goal difference last season, this campaign it worked in the Sky Blues' favour.

With Newcastle Jets' victory on Friday bringing them level on points with Sydney, only a loss by a two-goal margin or more would have denied them a finals spot and handed the Jets sixth place.

A Terry Antoni's screamer opened the scoring at the Sydney Football Stadium with Richard Garcia ensuring late drama with a winner in extra time.

Rostyn Griffiths scored a consolation goal for a Glory side playing only for pride.

Sydney fans praise retiring former skipper McFlynn.

The last time Sydney hosted Perth in February the cove unfurled a banner calling for Frank Farina's head, as the side languished outside the top six looking unlikely to make finals.

On Sunday however, the banner they held up was one of tribute, portraying retiring former skipper Terry McFlynn as the patron saint of the club as Sydney secured a spot in the play-offs in the side's last home game of the season.

And while Farina's future at the club is not yet assured, the coach is now guaranteed at least one more game at the helm.

Sydney dominated possession in the opening stages but it was the Glory who created the first chance of the match with Chris Harold just going wide with a an early strike.

The Sky Blues returned fire moments later with Terry Antonis putting keeper Jack Duncan to work.

And Antonis eventually broke through in the 38th minute with a clever Alessandro Del Piero pass setting him up to fire from range.

The Glory found the leveller moments before the half-time whistle with a Nebojsa Marinkovic corner getting past the Sydney defence and falling to Griffiths for the easy tap-in.

Sydney emerged from the break desperate to regain the lead with the Glory gloveman denying Del Piero his 11th goal of the season moments into the half while Richard Garcia forced another save from Duncan as the clock wound down.

Garcia eventually found the winner in the 93rd minute to seal victory.